<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .progress{position: relative; width:300px;margin:100px auto;}
        .progress_bg{position: relative; height: 10px; border: 1px solid #ddd; border-radius: 5px; overflow: hidden;background-color:#f2f2f2;}
        .progress_bar{background: #5FB878; width: 0; height: 10px; border-radius: 5px;}
        .progress_btn{width: 20px; height: 20px; border-radius: 5px; position: absolute;background:#fff;
            left: 0px; margin-left: -10px; top:-5px; cursor: pointer;border:1px #ddd solid;box-sizing:border-box;}
        .progress_btn:hover{border-color:#F7B824;}
    </style>
</head>
<body>
<div class="progress">
    <div class="progress_bg">
        <div class="progress_bar"></div>
    </div>
    <div class="progress_btn"></div>
    <div class="text">0%</div>
</div>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.min.js"></script>
<script>
    $(function(){
        var tag = false,ox = 0,left = 0,bgleft = 0;
        $('.progress_btn').mousedown(function(e) {
            ox = e.pageX - left;
            tag = true;
        });
        $(document).mouseup(function() {
            tag = false;
        });
        $('.progress').mousemove(function(e) {//鼠标移动
            if (tag) {
                left = e.pageX - ox;
                if (left <= 0) {
                    left = 0;
                }else if (left > 300) {
                    left = 300;
                }
                $('.progress_btn').css('left', left);
                $('.progress_bar').width(left);
                $('.text').html(parseInt((left/300)*100) + '%');
            }
        });
        $('.progress_bg').click(function(e) {//鼠标点击

            if (!tag) {
                bgleft = $('.progress_bg').offset().left;
                console.log(bgleft);
                left = e.pageX - bgleft;
                if (left <= 0) {
                    left = 0;
                }else if (left > 300) {
                    left = 300;
                }
                $('.progress_btn').css('left', left);
                $('.progress_bar').animate({width:left},300);
                $('.text').html(parseInt((left/300)*100) + '%');
            }
            console.log(e.clientX);
        });
    });
</script>
</body>
</html>